Metabolimeter



Au 24,1954 A. FLEISCH 2,687,128

METABOLIMETER Filed July 7, 1950 s Sheets-Sheet 1 INVENTOR. 44:45 is/ C42- A; FLEISCH METABOLIMETER Aug. 24, 1954 3 Sheets-Sheet 2 Filed July'7,- 1950 FIGJ! INVENTOR .i 141 862 251.: c-a/ z- 4, 1954 A. FLEISCH2,687,128

METABOLIMETER Filed July 7, 1950 Q 3 Sheets-Sheet a FIG. 1a

llvvglvron: 4 9 5113/ 467?!) 55/30 Patented Aug. 24, 1954 UNITED STATESPATENT OFFICE Claims priority, application Switzerland August 19, 1949 6Claims. 1 My present invention relates to improvements in metabolimetersfor determining the human basal metabolism factor by measuring theoxygen consumption.

For determining the human basal metabolism, it is conventional tomeasure the oxygen consumption in a certain time, e. g. in ten minutes.

These methods will indicate the volume of oxygen consumed in a givenlength of time, but such volume has to be reduced to normal conditions,i. e. to C. dryness and 760 mm. barometric pressure; for only underthese conditions one liter of consumed oxygen corresponds to thestandard of 4.825 calories. What is desired, however, is the number ofcalories supplied by the best person in 24 hours. Such conversion of theoxygen volume to normal conditions is timeconsuming for physicians andlaboratory staii and rather complicated so as to give rise to errors,Whilst the use of nomograms requires considerable practice. It would bea great advantage, therefore, if any conversion could be avoided.

The main object of my present invention is to provide a mechanical meansadapted to furnish the number of calories per 24 hours directly, i. e.without any conversion, on the basis of the deflections of thespirometer bell. According to whether the breathing curve is to berecorded or not, one or the other of two different mechanical means isused.

The apparatus according to my invention comprises a spirometer, a vesselfor absorbing the carbon dioxide, and a measuring device includingadjusting means for reducing the oxygen consumption value to dry air of0 C. and 760 mm. Hg and a scale for directly determining the number ofcalories for 24 hours corresponding to such reduced consumption value.

Two forms and a modification of my present invention are schematicallyshown in the accompanying drawing, in which- Fig. 1 shows a first formin elevation, partly in section,

Fig. 1a shows a detail of Fig. 1 on a larger scale,

Fig. 2 a second form,

Fig. 3 the measuring device of such second form,

Fig. 4 a modification of part of the said measuring device, and

Fig. 5 shows in dash lines part of the recorded movement of thespirometer bell during a test, and in full lines the correspondingmovement recorded with the aid of the modification shown in Fig. 4.

the bell I to a measuring device.

In Fig. 1 a metabolimeter is shown, of which the cylindrical,oxygen-filled spirometer comprises a bell I immersed in a vessel 2containing water, through which the inhaling-and-exhaling line 3 passes,which line in turn opens into the spirometer bell I. A cord 4 attachedcentrally to the ceiling of the spirometer bell, connects The connectinglink 5 is shaped like a circle segment in crosssection and is secured toa two-arm lever B at right angles to the axis thereof, which lever isfulcrumed at 1. In order to counterbalance the weight of the parts I and4-6 with respect to pivot a counterweight 8 is secured to the free endof arm ii. A third arm ii is rigidly connected to arm 5 at right anglesthereto, being pivoted at I and slotted to receive an axially movablesetting control tongue It. A cross pin II is rigidly secured to thelower end of tongue I0 and engaged in a groove of a swinging arm I2. Thelatter is pivoted at one end on a fixed hearing pin I3 and at the otherend, to a pointer IA. The stylus I5 of the latter is slidably disposedover a writing pad I6 which is mounted on a carriage I8 which is movableon rollers II transversely of the direction of movement of pointer I l.

The means for reducing the value of oxygen consumption to dryness, 0 C.and 760 mm. barometric pressure, are shown in Figure 1a. A temperaturescale 9a is provided on arm ii for cooperation with a barometric scaleIlla provided on slide Iii, the latter being axially movable on arm 9.For adjustment to dry air at 0 C. and 760 mm. barometric pressure themark on scale Ita showing the prevailing barometric pressure is broughtinto alignment with the mark on scale 90. showing the prevailingtemperature by axially moving the slide It.

The mode of operation of the apparatus descibed, otherwise is asfollows:

On inhaling, oxygen is abstracted from the spirometer bell I throughline 3, while the carbon dioxide of the air returning into the bell I onexhaling, is chemically absorbed. By reason of the increasing oxygenconsumption, the bell I gradually sinks into the water vessel 2, i. e.the bell I on inhaling moves downwardly for a certain amount, and onexhaling it moves upwardly for a smaller amount. The said movements aretransmitted through the connecting link. 5 and lever ii onto the arm 9,.and thence by the crosspin Ii of tongue It through the swinging arm Illonto the pointer I l and the pointer tip I5. The latter in accordancewith the transmitted movement of bell I, slides across the Writing padwhich moves at constant speed, and produces on said pad an ascendingsawtooth curve as shown by the dash lines 48-49-56-5! in Fig. 5. Theposition of the lower kinks 49, 5| of said curve with respect to acorresponding scale of said pad affords a direct reading of the 24-hourcalorie number corresponding to the oxygenconsumption. In order toreduce the oxygen-consumption figure to dryness, 0 C., and 760 mm. Hg,the tongue I?) carrying the barometric scale is so displaced in thebell-crank 9, prior to commencement of the test, that the existingbarometric pressure falls on that graduation of the temperature scalewhich corresponds to the existing temperature. Since such adjustmentcauses a corresponding resetting of cross-pin II with respect to itsaxial distance in arm 9 and to its axial distance in the groove of theslewing arm 12, the transmission ratio of the parts 9 and I2 of themeasuring device and, thus, the excursion of the sawtooth curve withrespect to the said scale of pad i6 is conformed to the said conditionsof dryness, 0 C. and 760 mm. barometric pressure.

In order to decrease the Weight of the apparatus and, thus, to render itportable, the recording of the movement of the spirometer bell may bereplaced by direct reading. Such portable form of my invention is shownin Fig. 2 and comprises a spirometer bell 26 which in cross-section isof circular sector shape. The said bell is pivoted on a pin 22 to anabsorption vessel 2|. The latter partly is filled, with soda lime 23 forabsorbing the carbon dioxide of the exhaled air, and comprises a watervessel 24 conforming in shape to bell 20, the Water serving for sealingthe bottom opening of bell 20. Since the spirometer bell 26 shown inFig. 2 constitutes a quarter of a circular cylinder, it may be swung invessel 24 through 90, i. e. between the horizontal and verticalpositions of the ceiling 26a of bell 20, and such swinging movement maybe limited by stops or dogs. A suction line 25 comprising a valve 26 andopening in an orifice 21, runs from the oxygen-filled bell 20 throughthe upper portion of vessel 24. The orifice 21 through an exhaling line29 which comprises a valve 28 and passes through the vessel 2!, isconnected to the inside of bell 20.

Before starting a test, the bell 20 is filled with oxygen from flask 32through a pipe 30 having a U-shaped portion disposed in the upperportion of vessel 24.

In order to prevent a further quantity of oxygen escaping from the flask32 and flowing through the pipe 30 into bell 20 during a test whichwould adulterate the test results should the valve 33 leak, apertures 3|are provided in the U-shaped portion of the pipe 30. The flow of theoxygen into the bell 26 is prevented by the water in the vessel 24 whichpenetrates the apertures 3| and acts as a sealing means. Port 34 may beopened to permit the oxygen to flow out of the pipe 30.

A barometer 35 is attached to vessel 2|, and a thermometer 36 to theceiling 20a of bell 20.

The means for converting the oxygen-consumption values to dryness, 0 C.and 760 mm. barometric pressure, conditions and for reading the calorienumber, are shown by way of example in Fig. 3. A rail 31 pivoted on thepivot axle 22 of bell 20 carries a scale 38 which is axially movabletherein. A barometric graduation b figured for conversion to 760 mm. Hg,and a temperature graduation t are provided on scale 38. The latterfurther carries a pointer 39 which is movable along the barometricgraduation b and has a terminal mark 46 for co-operation With thegraduation b, and a mark 4| secured to rail 3'! is intended forco-operation with the temperature graduation 75. Further, a reading disc42 is pivoted on the common axle 22 of both bell 26 and rail 31, andcarries a calorie graduation 42. The latter is intended for co-operationwith a reading knob 44 of pointer 39, is valid for a test period ofeight minutes for example, and allows to read olT the 24-hour calorienumber.

The mode of operation of the apparatus shown in Figs. 2 and 3 otherwiseis as follows:

At the beginning of the test, the spirometerbell 20 is filled withoxygen from flask 32 through line 36'. The oxygen-consumption value isconverted to dryness 0 C. and pressure conditions, for which purpose thescale 33 with its temperature graduation t is moved, in accordance withthe existing temperature, in rail 37 with respect to temperature mark4|, which procedure corresponds to a reduction of the oxygen temperatureto 0 C. The pointer 39 or respectively, its terminal mark 46 is movedalong the graduation b in accordance with the barometric pressure, whichprocedure corresponds to a reduction of the oxygen pressure to 760 mm.I-Igand dryness. The reading disc 42 then is turned about the axle pin22 so that the knob 44 at the beginning of the test stands on the zeroline of graduation 43. During the test, oxygen is taken from bell 20through the nozzle 21 and line 25 and valve 26, whereupon the exhaledair flows back into bell 26 through line 29, valve 23 and through thesoda.- line 23 which absorbs the carbon dioxide. The oxygen in bell 26thus is rhythmically decreased, as in the preceding example, and thebell 20 is turned counterclockwise on the axle pin 22. The knob 44 thusmoves rhythmically up and down across the scale 43. The exhalingposition corresponding to the lower kinks of said sawtoothcurve in thepreceding example, suitably is used as point of reading, since suchposition, as shown by the test, is much more constant than the inhalingposition. After eight minutes of test, the position of knob 44 withrespect to scale 43 is determined, whereby the 24-hour calorie numbermay be directly read off.

Owing to the continuous up-and-down move.- ment of knob 44 in Fig. 3,the readings in the respective terminal positions are rendered difilcut,whereby the accuracy of the reading may be impaired. In order toincrease the reading accuracy, the pointer 39 may be connected to thepivot axle 22, and thus to the spirometer 26 by means as shown in Fig. 4for example. An arm 45 is provided on bell 26 and comprises two stoppins 46 and 41 between which the pointer 39. is pivoted on the axle 22.During the reciprocating swing movement of the spirometer bell, thepointer 39 is taken along by the two spaced pins 46 and 47, whereby theknob 44 remains for a. moment in its terminal positions, depending onthe distance between the said pins. The extent of said distance and,thus, the duration of standstill of the pointer, may be varied byturning the pin 41 which is eccentrically mounted in arm 45.

By such means (Fig. 4) the usual saw-tooth line shown by the dash lines48-5l in Fig. 5, is changed to the stepped line shown by the full lines48, 53, 54, 55 and 5. The oxygen con.- sumption during one breath is thesame for both lines and corresponds to the distance 52. (Fig. 5.). whichfor example may amount to 22 cc.

What I claim as new and desire to secure by Letters Patent is:

1. In a metabolimeter, a carbon dioxide absorption vessel, a spirometercomprising a bell of substantially sectorial cross-section, a watercontainer defining a seal around the edge of the bell and meanssupporting the bell for pivoting movement in the container through atleast 90, and a measuring device comprising a carrier rail disposed inthe pivoting axis of the bell, a slide scale including a barometricpressure graduation for dry air and a temperature graduation movable insaid rail, a pointer on said scale movable along the barometricgraduation, a terminal mark on said pointer cooperating with thebarometric graduation, a mark on the rail cooperating with thetemperature graduation, and a scale for directly reading the calorienumber corresponding to the value of oxygen consumed in a 24 hour periodfor dry air at 0 C, and 760 mm. Hg.

2. A metabolimeter as in claim 1 wherein the calorie scale comprises agraduated disc dial pivotally mounted in the bell axis for adjustmentrelatively to the pointer.

3. In a metabolimeter, a spirometer comprising a bell adapted to befilled with oxygen, a water container defining a seal around the edge ofsaid bell, carbon dioxide absorption means, an inhaling and exhalingtube connected to said bell and said carbon dioxide absorption means,means supporting said bell fOr movement in the container, and ameasuring device including a pointer, means operatively connecting saidpointer to said bell for actuation by movement of the latter in responseto the consumption of oxygen from said bell and a scale cooperating withsaid pointer and directly indicating the calorie number corresponding tothe value of oxygen consumed in a 24 hour period for dry air at 0 C. anda pressure of 760 mm. Hg, said connecting means having calibrating meanstherein for varying the extent of the movement of said pointer relativeto said scale in response to movement of said bell thereby to providecompensation in the indication on said scale for whatever differencesmay exist between the actual temperature and. pressure and saidtemperature of 0 C. and pressure of 760 mm. Hg.

4. In a metabolimeter; the combination according to claim 3; whereinsaid calibrating means includes relatively movable members which, whendisplaced with respect to each other,

vary the extent of the movement of said'pointer -relative to said scalein response to movement of said bell, and cooperating scales and indiceson said relatively movable members for establishing the relativepositions of said members providing the necessary compensation forwhatever differences exist between the actual temperature and pressureand said temperature of 0 C. and pressure of 760 mm. Hg.

5. In a metabollmeter, a spirometer comprising a bell having across-section of substantially sectorial outline adapted to be filledwith oxygen, a water container defining a seal around the edge of saidbell, carbon dioxide absorption means, an inhaling and exhaling tubeconnected to said bell and said carbon dioxide absorption means, meanssupporting said bell for swinging movement through at least and ameasuring device including a pointer, means operatively connecting saidpointer to said bell for actuation bymovement of the latter in responseto the consumption of oxygen from said bell and a scale cooperating withsaid pointer and directly indicating the calorie number corresponding tothe value of oxygen consumed in a 2% hour period for dry air at 0 C. anda pressure of 760 mm. Hg, said connecting means including relativelymovable members which, when displaced with respect to each other, varythe extent of the movement of said pointer relative to said scale inresponse to movement or said bell and cooperating scales and indices onsaid relatively movable members for establishing the relative positionsof the latter providing the necessary compensation for whateverdifferences exist between the actual temperature and pressure and saidtemperature of 0 C. and pressure of 760 mm. Hg.

6. In a metabolimeter; the combination according to claim 5; whereinsaid pointer is supported for swinging about the same axis as said bell,and wherein said connecting means further includes two spaced stop pinsmoving with said bell and receiving said pointer therebetween to providelost motion between said bell and said pointer.

References Cited in the file of this patent UNITED STATES PATENTS

